export default {
  namespaced:true,
  state:() =>({
    // 购物车的数组，用来存储购物车中的每个商品的信息对象
    // 每个商品的对象都包含如下六个属性
     // { goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
     cart:JSON.parse(uni.getStorageSync('cart') || '[]')
  }),
  mutations:{
    addToCart(state,goods){
     const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
     // console.log(findResult)
     if(!findResult){
       state.cart.push(goods)
     }else{
       findResult.goods_count++
     }
     // console.log(state.cart)
     this.commit('m_cart/saveToStorage')
    },
    saveToStorage(state){
      uni.setStorageSync('cart',JSON.stringify(state.cart))
    },
    // 更新购物车商品中的勾选状态
    updateGoodsState(state,goods){
      const findResult = state.cart.find(x=>x.goods_id === goods.goods_id)
      if(findResult){
        findResult.goods_state = goods.goods_state
        this.commit('m_cart/saveToStorage')
      }
    },
    // 更新商品的数量
    updateGoodsCount(state,goods){
      const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
      if(findResult){
        findResult.goods_count = goods.goods_count
        this.commit('m_cart/saveToStorage')
      }
    },
    // 根据id删除对应的商品
    removeGoodsById(state,goods_id){
     state.cart = state.cart.filter(x => x.goods_id !== goods_id)
      this.commit('m_cart/saveToStorage')
    },
    // 更新购物车中所有商品的状态
    updateAllGoodsState(state,newState){
      state.cart.forEach(x => x.goods_state = newState)
      this.commit('m_cart/saveToStorage')
    }
  },
  getters:{
    // 购物车所有商品的总数量
    total(state){
      // let c = 0
      // state.cart.forEach(x => c += x.goods_count)
      // return c
       return state.cart.reduce((total,item)=>total += item.goods_count,0)
      
    },
    // 购物车已勾选商品的总数量
    checkedCount(state){
     return state.cart.filter(x => x.goods_state).reduce((total,item) =>total += item.goods_count, 0)
    },
    // 已勾选商品的总价格
    checkedGoodsAmount(state){
     return state.cart.filter(x => x.goods_state).reduce((total,item) =>total += item.goods_count * item.goods_price ,0).toFixed(2)
    }
  }
}